1. Field of the Invention
This invention relates generally to electronic temperature sensors for measuring the temperature of fluids remote from a recording device. The present invention is particularly adapted for measuring fluid temperature at a downhole location within the bore of an oil or gas well and recording the temperature at the well surface.
2. Description of the Prior Art
For many years, operators of oil and gas wells have been interested in measuring various physical parameters associated with each well in order to understand the characteristics of the underground hydrocarbon producing formation and to optimize the production of hydrocarbons from each well. Some of the more frequently measured parameters are:
a. bottom hole pressure and surface pressure while the well is both flowing and shut in; PA1 b. flow rate versus pressure and direction of fluid flow; PA1 c. pressure versus time both during pressure buildup after shutting in a well and pressure drawdown when flow is resumed; PA1 d. oil versus gas ratio in the production fluid; and PA1 e. fluid temperature at which each of the above tests is conducted.
U.S. Pat. No. 4,107,697 titled Pressure Recorder with Power Conservation Means and U.S. Pat. No. 4,161,782 titled Microprocessor Computerized Pressure/Temperature/Time Down-Hole Recorder disclose well tools which can measure and record some of these parameters. Both patents are incorporated by reference for all purposes within this application. Accurate determination of fluid temperature is critical for the validity of any well testing.